Pressure-fluid motor



PRESSURE FLUID MOTOR Filed D60. 30. 1927 12701672207.- ZJZmer 6? Ga Patented Nov. 26, 1929 UNITED STATES lJE'ZAlih PATENT ELMER G. GARTIN, F CLAREMONT, new 'I-rAMrsnIRE, ASSIGIIQR Fro SULLIVAN MACHINERY COMPANY, A CORPORATION or mnssncnusnrrs PRESSURE-FLUID MOTOR Application filed Decem ber so, 1927.

This invention relates to" pressure fluid motors, and more particularly pertains to pressure fluid motors of the reciprocable piston type.

An object of this invention is to provide an improved pressure fluid motor. Another object is to provide an improved pressure fluid motor of the reciprocable piston type having improved fluid distribution means.

Yet another object is to provide an improved pressure fluid motor having improved fluid distribution means of the differential sleeve valve type, the differential "sleeve valve being arranged in axial alinement with the cylinder bore. Still another object of thisinvention is to provide an improved pressure fluid motor of the valved type having improved and simplified fluid distribution means and improved means for effecting movements of the valve. Another object is to provide an improved pressure fluid motor of the impact type which is exceedingly efiicient, rugged and compact and which maybe manufactured at a minimum of expense, the parts being comparatively few and the fluid distribution means relatively simple. These and other objects and advantages of this invention will, however, subsequently more fully appear.

In the accompanying drawing there is shown for purposes of illustration one form which the invention may assume in practice.

In this drawing Fig. 1 is a central, longitudinally extendi'ng, sectional view illustrating the improved pressurefluid motor.

Fig. 2 is a view similar to Fig. 1 illustrating the motor piston and distribution valve in a diflerent position.

In the llustrative embodiment of the invention there is shown a pressure fluid motor comprising a cylinder 1 having a bore 2 containing a reciprocable piston 3. Asshown the piston 3 has an enlarged head {i slidably fitting the bore 2 and a reduced forwardly projecting portion or extension 5 reeiproeably mounted in a bore 6 formed in afront buffer rin 7. As shown the buffer ring 7 is mounted within the bore 8 formed within the forward end of the cylinder and abuts at its rear end a shoulder 9' formed at the intersection of the Serial No. 243,726.

bores 2 and 8. p The rear end of the cylinder and extending transversely of the rear motor head 10. The throttle valve 11 has formed therein a central chamber 13 having communication with the source of pressure fluid supply and cOmmunicating'with this chain ber 13 and traversing the wall of the valve is a port 14 which, when the throttle valve is in the position shown, connects the cham= ber 13 with a passage 15; formed in the motor head 10. Communicating with the passage 15 and extending longitudinally of the cylinder 1 is a passage 16 in turn communicating through "a radial port 17 with the forward end of the cylinder bore 2. In accordance with this illustrative embodiment of the invention there is shown formed within the rear motor head 10 a valve chamber 18 located in aixal alinement with the cylinder bore 2. The rearward end of the valve chamber 18 is closed by a suitable cap member 19 suitably held in position within the motor head 10. As shown the valve chamber 18 comprises stepped bores 20 and 21 formed within the motor head 10 and stepped bores 22 and 28 of different diameters than the bores 20 and 21 and formed within the cap member 19'; The bore 21 communicates with the rear end of the cylinder bore 2. Disposed between the bores 22, 28 inthe cap19 is an enlarged annular recess 24 connected directly to atmosphere through alateral port 25. Also disposed between the bores 20 and 21 in the head member 10 is an annular recess 26 connected by a lateral passage 27, longitudinal passage 28', and lateral port 29 with the cylinder bore 2, the port 29 communicating with the cylinderbore at a point substantially intermediate its ends. In this instance a restricted passage 30 formed in the head member 10 connects the fluid supply passage 15 with the bore 20, the passage 30 having pressure fluid motor is as follows: Let it be assumed that the parts are in the position shown in Fig. 1 with pressure fluid flowing continuously from the throttle valve 11 through port 14,-, passages 15, 16, and port 17 to the forward end of the cylinder bore 2. The pressure acting on the forward area of the head 4; of the piston causes the latter to move rearwardly. At this time the cylinder bore at the rear end of the piston is exhausted to atmosphere through the bore 21 and through the sleeve valve 31 into the annular recess 24 and thence through the lateral passage 25 to atmosphere. As the piston 3 moves rearwardly the port 29 is uncovered and pressure fluid then flows from the forward end of the cylinder bore through the port 29, passage 28, and passage 27 to the annular recess 26. The pressure fluid acting on the spool 32 of the valve throws the latter from the position shown in Fig. 1 to the position shown in Fig. 2, the area of the forward face of the spool. 32 being greater than the area of the rearward face of the spool on which pressure fluid flowing through passage 30 continuously acts. The exhaust from the rear end of the cylinder bore through port 25 is then out off by the sleeve portion 35 entering the bore 22. At the same time communication between the passage 27 and the rear end ofthe cylinder bore is opened as the sleeve portion 33 moves rearwardly from the bore 21. Pressure fluid then flows from the annular recess 26 through bore 21 to the rear end of the cylinder bore wherein the fluid acts on the large rear area of the piston head- 4, which is materially greater than the opposed front area, thereby causing the piston to be moved rapidly for ward to effect its working stroke. As the piston moves forward the port 29 is covered by the piston head, cutting off the supply by pressure fluid to the rear end of the cylinder bore and the piston 3 then moves solely under the expansive action of the fluid within the rear end of the cylinder bore and momentum. As the piston 3 continues its forward movement the pressure within the rear end of the cylinder bore and consequently within the recess 26 drops materially so that the constant pressure acting on the rear surface of the spool 32 of the valve overcomes the pressure acting on the front valve surface and thereby causes the valve to be shifted forward from the position shown in Fig. 2 to the position shown in Fig. 1, again connecting the rear end of the cylinder bore to exhaust. The above cycle of events continues throughout the normal operation of the motor.

As a result of this invention it will be noted that an improved pressure fluid motor is provided having improved and simplified fluid distribution means whereby the power and efficiency of the motor is materially increased. It will further be noted that a fluid motor is provided of a simple, rugged and compact character having comparatively few component parts and which may be manufactured at a minimum of expense. These and other uses and advantages of the improved pressure fluid motor will be clearly apparentto those skilled in this art.

lVhile I have in this application specifically described one form which the invention may assume in practice, it will be understood that this form of the same is shown for purposes of-illustration and that the invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by LettersPatent is: I

1. A pressure fluid'motor comprising a cylinder having a bore and a piston ,reciproeable therein having differential pressure areas, and fluid distribution means for effecting reciprocation of said piston-comprising a differential sleeve valve for controlling the supply and exhaust of pressure fluid for the rear end of the cylinder bore and having opposed differential front and rear pressure areas, the bore of said sleeve valve, in apredetermined position of the latter, constituting a passage for conducting exhaust from the rear end of the cylinder, means forsubjecting the rear pressure area on said valve to constant pressure, means for subjecting the opposed front pressure area on said valve to pressure within the front end of the cylinder here while the piston is still remote from its rear most position, and means for supplying pressure constantly to the front end of said cylinder bore.

2. A pressure fluid motor comprising a cylinder having a bore and a piston reciprocable therein having differential pressure areas, and fluid distribution means for effecting reciprocation of said piston comprising adiif'erential sleeve valve arranged in axial alinement with the cylinder for cont-rolling the supply and exhaust of pressure fluid for the rear end of the cylinder bore and having opposed differential front and rear pressure areas, the bore of said sleeve valve, in a predetermined position of the latter, constituting a passage for conducting exhaust from the rear end of the cylinder, means for subjecting the rear pressure area on said valve to constantprestherein having differential pressure areas,

front end of the cylinder. bore while said piston is materially spaced from said valve, and

means for supplying pressure continuously to the front end of, said cylinder bore.

3. A pressure fluid motor comprlslng a cylinder having abore and a piston reciprocable and fluid distribution means for effecting reciprocation of said piston comprising a pas-v sage'forsupply ng fluid continuously to the "forward end of the cylinder bore to act on the forward area of said piston, a hollow sleeve valve havrngopposed dlflerential pressure areas for controlling the supply and ex-.

haust of fluid for the rear end of the cylinder bore, the bore of said sleeve valve, in a predetermined position ofthe latter, consti;

tuting a passage for conducting exhaust from the rear end of the cylinder, means including a piston controlled passage for supplying fluid from the cylinder bore to the front.

area on said valve for throwing said valve in one direction, and means for throwing said valve in the opposite direction by constant pressure acting on the opposed rear area on said valve.

4:. A pressure fluid motor comprising a cylinder having a bore and a piston reciprocable therein having diflerential pressure areas, and fluid distribution means for effecting reciprocation of said piston comprising a passage for supplying fluid continuously to the forward end of the cylinder bore to act on the forward area of said piston, a hollow sleeve valve having opposed differential pressure areas for controlling the supply and exhaust of fluid for the rear end of the cylinder bore, the bore of said sleeve valve, in a predetermined position of the latter, constituting a passage for conducting exhaust from therein having differential pressure areas,

and fluid distribution means for effecting reciprocation of said piston comprising a passage for supplying fluid continuously to the forward end of the cylinder bore to act on the forward area of said piston, a hollow sleeve valve having opposed differential pressure areas for controlling the supply and exhaust of fluid for the rear end of the cylinder bore, 1

means including a piston controlled passage for supplying fluid from the cylinder bore to the front area on said valve for throwing said valve in one direction, means for throwing said valve in the opposite direction by constant pressure acting on the opposed rear area on said valve, and exhaust means for the rear end of the cylinder bore controlled by said I, valve whereby the exhausting fluid flows through said valve to atmosphere.

6'. in a pressure fluid motor comprising a cylinder having a bore and a piston reciprocable therein having a relatively large rear pres,- sure area and a relatively small front passage area, and. fluid distribution means for effectingreciprocation of saidipiston comprising a nollow sleeve valve having opposed differential pressure areas for controlling the supply and exhaust of fluid for the rear end of the cylinderbore, the bore ofisaid sleeve valve, in a predetermined position of the latter, constituting a passage for conducting exhaust fromthe rear end of-the cylinder,

means for subjectingthe front pressure area on said valve to the pressure within the front end of said cylinder bore, means for subjecting the opposed rear pressure area on said valveto constant pressure, andmeans for supplying pressure constantly to the front end of the cylinder bore. 7

, 7. In a pressure fluidmotor comprising a cylinder having a bore and a piston reciprocable therein having a relatively large rear pressure area and a relatlvely small front pres sure area, and fluid distribution means for elfectlng reclprocation of said p1ston comprising a hollow sleeve valve arranged in axial alinement withthe cylinder bore and having opposed differential pressure areas for controlling the supply and exhaust of fluid for the rear end of the cylinder bore, the bore of said sleevevalve, in a predetermined position of the latter, constituting a passage forconducting exhaust from the rear end of thecylinder, means for subjecting the the rear end of the cylinder, means including a piston controlled passage for supplying,

front pressure area on said valve to the pressure withinithe front end of said cylinder here, means for subjecting the opposed rear ,pressure area onsaid valve to constant pressure, and means for supplying pressure con- ,stantly to the front end of the cylinder bore.

8. In a pressure fluid motor, a cylinder 'having a bore and a piston reciprocable therein having a relatively large rear pressure area and a relatively small front pressure area, and fluid distribution means for effecting reciprocation of said piston comprising a hollow sleeve valve having opposed differential pressure areas, said valve controlling the supply and exhaust of fluid for the rear end of I the cylinder bore, means for supplying fluid continuously to the forward end of the cylinder bore, means for sub ect1ng the rear pressure area on said valve to constant pressure to throw said valve forward toconnect the rear en'd'of the cylinder bore with the exhaust, and means controlled by said piston for subjecting the forward pressure area on said valve to the pressure within the front end of said bore to throw said valve rear- .vardly to connect the rear end of the cylinder bore with the front end of the Cylinder bore.

9. In a pressure fluid motor, a cylinder having a bore and a piston reciprocable therein havinga relatively large rear pressure area and a relatively small front pressure area,

and fluid distribution means for effecting reciprocation of said piston comprising a hollow sleeve valve having opposed differential pressure areas and a central opening, said valve controlling the supply and exhaust of fluid for the rear end of the cylinder bore,

means for supplying fluid continuously to the forward end of the cylinder here, means for subjecting the rear pressure area on said bore.

10. A pressure fluid motor comprising a cylinder, a piston having a head providing differential pressure areas reciprocable in said cylinder, a valve chest so positioned with reference to said cylinder that the axial lines of said cylinder and valve chest are parallel I to the same straight line, a sleeve valve reciprocable axially of said valve chest and having its bore adapted to serve 1n one position of said valve as an exhaust passage, said sleeve valve having between and spaced from the ends thereof opposed difierentlal pressure areas, sa1d valve chest communicating at one end with the cylinder bore and adjacent its other end with the atmosphere, means for conducting motive fluid continuously to the end of the cylinder remote from the valve chest, means for-transmitting pressure fluid continuously to one of the differential pressure areas on the valve, and meanseontrolled, by said piston head for connecting one end of said cylinder bore with the other of the differential pressure areas on the valve.

' cylinder, a piston having a head providing diflerent1al pressure areas reclprocable in 11. 'A pressure fluid motor comprising a said cylinder, a valve chest so positioned with reference to said cylinder that the axial lines of said cylinder and valve chest are parallel to the same straight line, a sleeve valve reciproeable axially of said valve chest and having its bore adapted to serve in one position of said valve as an exhaust passage, said sleeve valve having between and spaced from the ends thereof opposed differential pressure areas, said valve chest communicating at one end with the cylinder bore and adjacent its other end with the atmosphere, means for conducting motive fluid continuously to the end of the cylinder remote from the valve chest, means, for transmitting pressure fluid continuously to one of the differential pressure areas on the valve, and common means controlled by said piston head for connecting the front end of said'cylinder bore with g the other of thediiferential pressure areas on the valve and for conducting fluid to the valve chest for transmission through the end thereof to said cylinder.

In testimony whereof I aflix my signature.

ELMER e. GARTIN. 

